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shingle roof cleaning; any experience with commercial sprays???

Posted by jaansu (My Page) on
Sun, Aug 18, 13 at 22:09

I note there are a number of products for cleaning roofs of black streaks (Spray and Forget, Defy, Zinsser Jomax). I have some minor streaking I'd like to clean by spraying something without needing to use any brushing. Anyone have any experiences, good or bad, with such products?


Follow-Up Postings:

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RE: shingle roof cleaning; any experience with commercial sprays?

It's usually an algae. Bleach and water mixed 1:2 (ie 1 gal bleach, 2 gal water) will make it go away, pretty much instantly. Apply with a garden sprayer. No need for anything fancier or more expensive. I've heard that copper, lead or zinc strips mounted at the peak will prevent regrowth, but have no experience with this.


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RE: shingle roof cleaning; any experience with commercial sprays?

Thanks, I've mixed reviews to strong base on shingles. The commercial mixes seem to make use of other oxidants and are less likely to impact my plants.

I put up zinc strips but they haven't entirely protected the roof. Trouble is that relatively little rain washes down the zinc ions since they are near the top of the roof.


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RE: shingle roof cleaning; any experience with commercial sprays?

If you are worried about plants, paint some of the perspective cleaners on a sample and see what happens. Be reasonable. Wet them before and rinse them promptly. If you are worried about shingles, soak some shingles in a solution for an extended period and see if there are any effects. I think that in both cases, you will see that there is no impact.


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RE: shingle roof cleaning; any experience with commercial sprays?

that's a great idea, do a stability test before starting. Thank you.


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RE: shingle roof cleaning; any experience with commercial sprays?

Been there, done that...hopefully I won't have to do it again.

Had a company come out and do a "test drive" on part of the roof. Same thing, a slight change but nothing significant. I then tried a couple of commercial solutions that had little effect on my roof.

I ended up using 1:2 bleach to water with a squirt of Dawn dishwashing liquid in a garden spray bottle.

I sprayed a section, and let it sit, then rinsed. Some improvement, but not a what I was looking for.

I ended up having to lightly scrub the shingles with a very soft bristle brush, just to agitate the liquid against the granules. I really didn't loosen any granules. Just a soft scrubbing.

I thoroughly watered the foundation plants (mostly holly) and the grass near the house both before and after treating the roof. Didn't lose any plants or grass. I do have gutters and downspouts, I gave the gutters a good hosing afterwards.


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RE: shingle roof cleaning; any experience with commercial sprays?

Alkalinizing the solution with TSP or a substitute can increase the effectiveness of the bleach considerably. TSP is not available in some areas due to its impact on water quality. Substitutes, sodium meta silicate, borax and sodium carbonate, have varying effectiveness.

You might not need the higher effectiveness so much for removing the black or algae (most common and will not harm the shingles). For moss and lichen (that will damage shingles), you might find it useful. You will probably want it for black mold too,

Wetting the surface of the plants is likely more important that watering the soil. Use caution when using strong bleach solutions, especially if alkalinized further. Use eye protection, and don't breathe the dust. The solution may cloud glass and is corrosive to metals so rinse metals and glass promptly.


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RE: shingle roof cleaning; any experience with commercial sprays?

Depending on condition of stains, different cleaning agents are being used for cleaning roof shingles. We have used Roof Cleaner OX which is Oxygen Powered, environmentally green eco-cleaner that works well with roof algae stain removing power.


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RE: shingle roof cleaning; any experience with commercial sprays?

thank you all. I decided to use a product I found at HD that claims it is safe but required 6-9 months after spraying to remove the algae stains. As my roof has barely noticeable problems, I shall wait and see the results next spring or so. Otherwise it is the TSP/bleach route.


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RE: shingle roof cleaning; any experience with commercial sprays?

What was the product? Algae would be expected to bleach out and slough off if it is all dead, but it would take time. Bleach will decolorize and kill in one swoop. I expect that your product is an algicide or algistat. I wonder if it has some residual effect.


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RE: shingle roof cleaning; any experience with commercial sprays?

I don't know if I am supposed to mention product names but they sell Spray & Forget. The reviews seem to look good and my reading the MSDS (I'm a chemist) suggests it isn't too toxic or corrosive. Must admit, very easy if it works. Just spray it on and you are done. I'll try to post back by next spring to give a report.


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RE: shingle roof cleaning; any experience with commercial sprays?

"Cationic surfactants" I think it will not work very well with hard water.


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RE: shingle roof cleaning; any experience with commercial sprays?

There are several different reasons why someone may decide to clean their roof. The most common reason is to restore the appearance of the roof as well as the overall curb appeal of the home.

Roof Cleaning Company


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